Process of producing polyvalentmetal hydrocarbon sulfonate



Patented Nov. 16, 1948 CROSS REFERENCE PROCESS OF PRODUCING POLYVALENT-METAL HYDROCABBON SULFONATE Ulric B. Bray, Pasadena, Calif.

No Drawing. Application October 23, 1944. Serial No. 560,030

21 Claims. (Cl. 260-504) This invention relates to lubricating and rustpreventing compositions, and also to processes for manufacture of suchcompositions.

Important objects of the invention are to produce compositions which areexceptionally efficient for lubrication purposes, especially in severeservice engines, and for the prevention of rust under severe conditionsof use. Another object is to provide methods for the easy manufacture ofconstituents employed in such compositions, particularly the productionof oil-soluble, water-insoluble petroleum sulfonates substantially freefrom inorganic salts and water-soluble or kindred sulfonates which aregenerally conducive to rust formation, and to undue wear and corrosionin internal combustion enaines. 1n the preparation of some rustpreventing compounds and lubricants, and in the preparation of somelubricants for severe service uses and for similar lubricating uses, ithas been a practice for several years to employ various metal salts ofsulfonic acids derived from petroleum fractions in connection withsulfuric acid treatment of such petroleum fractions. These sulfonicacids, and their salts are well known in the petroleum industry. Thosemost commonly used for the present purpose are the oil-soluble acidsknown as mahogany acids which are found in solution in a supernatant oillayer which accumulates above an acid sludge layer upon settling of abatch of petroleum lubricating oil following sulfuric acid treatment.The sulfuric acid treatment of petroleum lubricating all results also inthe production of other sulfonic acids, known as "green acids, which areprimarily water-soluble and are, therefore, found chiefly in the acidsludge layer. However, some of these watersoluble green acids are foundin the presence of the oil-soluble mahogany acids in the oil layer andare objectionable for certain purposes. Possibly these vagrantwater-soluble sulfonic acids pass into the oil layer because they are atthe same time slightly oil-soluble, or because they are to that extentsolubilized by the action of the mahogany acids. As a result, theseobjectionable water-soluble green acids are carried over as sulfonateinto the oil-soluble sulfonate which is commonly placed upon themarketas the sodium salts of the mahogany acids. For the purpose of preparingrust preventing compounds and severe service lubricants, these sodiummahogan acid salts are commonly converted by metathesis into alkalineearth metal sulfonates, usually the calcium salts. The calcium salts ofthe true mahogany acids appear to be almost entirely insoluble in wateralthough oil-soluble. But the resultant calcium salts of the greenacids, which are readily water-soluble, are apparently also oilsolublein the presence of mahogany acid salt. Because of theirwater-solubility, they are obiectionable in rust preventives and inlubricating oils where moisture may be encountered. because they appearto weaken the resistance to water of an oil mm on metal, possiblythrough favoring the formation of a water-continuous emulsion; whereasthe water-insoluble, oil-soluble calcium salts of the true mahoganyacids, when operating in the presence of water to form emulsions, resuitin emulsions where oil is the continuous phase. In the case ofoil-continuous emulsions, the oil preferentially wets iron or steelsurfaces with the result that the water present in the emulsion does notwet the metal and rusting is avoided. On the other hand. where thechemical environment producu water-continuous emulsions, the water phasedisplaces the oil from the metal surface, thereby reducing or destroyingthe rust inhibiting effect of the oil. Even though the oil-soluble,water-insoluble sulfonates greatly predominate, nevertheless,appreciable proportions of water-soluble sulfonates result incorresponding rusting eiiects, even a relatively small proportion of thewater-soluble sulionate resulting in excessive water corrosion, to theextent that-products fail to give the full degree of protection requiredin severe service, such as in military and naval operation.

A primary object of the present invention is to eliminate thewater-soluble sulfonates above-described. or at least to reduce them tosuch an insignificant Proportion that their presence is not detrimental.Another important object is to produce a finished sulfonate free frominorganic salts such as sodium chloride calcium chloride and sodiumsulfate that may be formed by metathesis or be present as impurities.

I have discovered that the water-soluble sulfonates which ordinarily arepresent in commercial oil-soluble sulfonates of the mahogany acid type,such as those commonly placed on the marhot in the form of oil-solublesodium sulfonates.

can be so completely eliminated from the alkaline earth metal productproduced by metathesis as to be either not present at all or at leastpresent in such reduced quantities that their presence and eflect arenot detrimental. This purification of the oil-soluble sulfonatee isaccomplished by diluting the batch of sulionates underlain: metathesisor purification with a smallpencentase.

example, around 2% or 3% or in the order of OR IN 252/33 SEARCH ROQNabout 0.2% to of the total batch being treated, of a water-insoluble,oil-soluble aliphatic alcohol or other oxygen-bearing organic solventhavlngappropriate boiling point and sufiiciently low viscosity andpreferably capable of producing viscosity reduction efi'ects. Bysuitable boiling point, it is intended to signify a material Whoseboiling point is below the decomposition temperature of the sulfonate sothat the diluent material may be eliminated from the product byvaporization. In general, this signifies a boiling point not materiallyin excess of 350 F., inasmuch as the initial decomposition temperatureof a sulionate such as calcium sulfonate is in the neighborhood of 450'F. The object in using material of relatively low viscosity is to reducethe viscosity of the sulfonate so that it does not thicken or curdduring the conversion operations.

This class of diiuents is best represented commonly by amyl alcohol (e.g. fusel-oil) and butyl alcohol. Both of these materials boil severaldegrees above the boiling point of water, and they are almost entirelyinsoluble in water. However. other alcohols that may be employed are thehexanols, the pentanols, and also the octanols (especially2-ethylhexanol) In general, I may use any oxygen-containing organiccompound possessing four or more carbon atoms, which is oil-soluble,water-insoluble and possesses a boiling point not appreciably above 350F. and preferably not exceeding about 400 F. so far as is known, allaliphatic alcohols containing four or more carbon atoms and having asufiicently low boiling point are usable. Some times it is desirable orpermissible to leave the alcohol or a substantial proportion thereof inthe finished sulfonate composition. In such a case, the boiling point oithe alcohol may not be a limiting factor in its use, as in the case ofz-ethylhexanol.

In it broadest aspect, one phase of the invention resides in employingas a diluent in the purification or conversion of the sulfonates anoilsoluble, water-insoluble organic compound consisting only of carbon,hydrogen and oxygen, the diluent or solvent having a boiling point belowthe decomposition temperature of the sulfonates. In general, thesematerials contain at least four carbon atoms per molecule, and, in orderto avoid too high a viscosity, they will ordinarily contain not morethan about eight carbon atoms per molecule. More specifically, andprimarily, the invention resides also in the definitely preferred classof oil-soluble, water-insoluble aliphatic alcohols whose boiling pointis below the decomposition point of the sulfonates. These materials alsocontain at least four carbon atoms per molecule and ordinarily not toexceed eight carbon atoms per molecule in order to avoid excessiveviscosity. The two members which constitute an outstanding preferredclass are butyl alcohol and ethyl alcohol, these being especiallypreferred because of their relatively low boiling point, low viscosityand great effectiveness, and also because of their ready availabilityand relatively low cost. While aliphatic alcohols of four or five carbonatoms may be preferred, I may also use alcohols of the polymethyleneseries such as cyclohexanol and methyl cyclohexanol, and of the benzenese. ries such as phenol and cresol. Alcohols of the aliphati typecontaining ring constituents, such as benzy l alcohol and furfurylalcohol, may be also used. These materials are normally liquid and arein general solvents for the mineral oils and oil-soluble sulfonatesinvolved.

employed; that is, any sodium mahogany acid salt whichcharacteristically contains a consid-.

erable proportion of mineral .oil commonly carried over into thecommercial product from the mineral oil fraction which was originallytreated in preparing the sulfonate. Such a commercial sulionate isordinarily quite viscous or even semisolid at normal temperatures andcontains varying amounts of mineral oil, for example, 15% to as much as75% of the oil. This commercial concentrate is often further dilutedwith mineral oil as desired to reduce viscosity and facilitate handling. It is sometimes desirable however. to employ no additionalmineral oil or as small a proportion as possible in order to reduce thebulk be ing handled or; to produce a product of very vis-- cous orresinous consistency.

The sodium sulfonates in the oil carrier are all water-soluble ordispersible in water. In practicing my invention, one volume ofsulfonate-oil mixture is dispersedin 1 to 5 or more volumes of water,preferably ator near the boiling point of water. This solutionor-dispersion is thewatercontinuous type. For the purpose ofv conversioninto an oil-soluble, water-insoluble metal suitonate, a water solutionof an appropriate metal salt is then added and mixed, with the aqueoussuli'onate-oil dispersion. at a temperature of about 210 F.,agitationbeing employed to insure com- 'plete distribution.characteristically, a watersoluble calcium salt is used. such as calciumchloride in a, water solution of 40% concentration, a proportion of thesolution being added sufllcient to provide at least a slight excess ofcalcium chloride. Other proportions oi. solution to afford asaitsfactory working volume of water and containing the salt inconcentrations to yield any desired excess may be employed. The agitatedheated mass usually quickly develops into a characteristic thick ordoughy mass of oil-continuous emulsion as the water-insoluble calciumsulfonate forms. As a result subsequent settling produces relativelylittle separation, or at least very poor separation. Consequently, thewater-soluble calcium sulfonates which are formed from the green acidsalts during metathesis are mechanically retained in the massofoil-continuous emulsion. Also, the water phase dispersed as dropletsthroughout the oil-continuous mass contains the dissolved inorganicsalts representing original impurities suci as sodium sulfate, sodiumchloride produced by metathesis. and excess calcium chloride. It isextremely dimcult or practically impossible to wash out or settle outthe briny water phase at this stage by the conventional method=.Heretofore, it has been the practice to evaporate the entire amount ofwater entrained in the oilcalcium sulfonate mass, and to remove as muchas Possible of the inorganic salts and other impurities from thedehydrated oil-sulfonate mixture by mechanical means. such ascentrifugin filtering in the presence of a filter aid such as II I...)

zoo-42a t'ROSS REFERENCE aasaeco diatomaceous earth. Naphthl. issometimes addQ before, during or after the dehydration in order toiacilitate handling and removal of crystallized salts and otherimpurities. Such operations are laborious, expensive, and usually do notremove all inorganic salts from the finished product. Obviously, littleor no rejection of watersoluble metal sulfonates is accomplished.

According to the improvement of this invention, a small quantity of thedescribed oil-soluble, water-insoluble diluent alcohol or otherindicated oxygen-bearing organic compound is added before, during orafter the metathesis, with agitation so as to be thoroughly distributedthroughout the mass being treated. Sufilcient organic compound is addedto obtain good breaking of the emulsion, which seems to vary somewhatwith the sulfonate, the amounts of oil and water present and amount ofexcess calcium chloride used. Ordinarily, 0.2% to 3.0% of commercialfusel-oil (iso-amyl alcohol) based on the volume of the kettle contentsis employed. For somewhat faster operation, a greater proportion such asor even up to may be added, especial- 1y where the alcohol is to berecovered upon subsequent evaporation. Upon completing distribution ofthe alcohol in sumcient quantity through the mass, and stoppingagitation, the phases quickly break, and separation by settling followswith comparative rapidity. The separation is so complete that a distinctline forms between the resultant supernatant oil phase in which most ofthe alcohol and all of the water-insoluble, oil-soluble calciumsulfonates have dissolved. and the lower water phase in whichwater-soluble calcium sulionate has dissolved along with excess calciumchloride and the resultant sodium chloride formed in the conversion,together with any other watersoluble impurities present. such as sodiumsulfate and sodium sulflte. Separation of the phases may beaccomplished, if desired, by centrifuging the mass after mixing in thealcohol, using for example a de Laval separator; but I have foundsettling in a. suitable vessel as described below to be satisfactorywhen the .proper alcohol is used in suitable amount.

After settling either the supernatant oil layer containing the diluentalcohol and the dissolved water-insoluble sulfonates may be decantedfrom the water layer, or the water layer may be withdrawn from thetreating vessel leaving only the oil and alcohol layer. In either event,the oil layer is heated to expel any entrained water and the diluentalcohol, which alcohol may be passed to a recovery system if desired.Should an alcohol have been employed whose boiling point too close- 1yapproximates the decomposition temperature of the sulfonate, theevaporation of the diluent may be-oonducted under appropriate vacuum.

The resultant solvent-free concentrate of calcium-sulfonate in oi.apparently contains little or no water-soluble sulfonate and noinorganic salts. In other words a mahogany acid soap concentratecomparatively free from green acid soaps and inorganic salts isproduced. Or, in any event, the oil-containing concentrate possessesinsufllcient objectionable sulfqnates or other impurities to interferewith the rust preventing and/or detergent properties of compoundsproduced therefrom.

If it should be that, in the heating of the oil layer to expel thediluent, a. product is yielded that requires clarification, it may becentrifuged, or a small amount or filter aid such as diatomaceous earthmay be added and commingled with the 6masathem'assbeingthenfilteredtoyieldaclear final product. For example,small amounts of crystallized salts, trapped in the oil-sulfonatesolution following expulsion of solvent and of water that contained thesalts and was entrained in the oil-sulfonate layer during settling, willbe removed. So complete however is removal of such salts in the waterlayer, which separates upon the described alcohol treatment, that, inbatches containing 900 lbs. of excess CaCh and other salts. less than 50lbs. (sometimes as little as 10 lbs.) is trapped through the medium ofentrained water, this being easily removed by centrifu-gation; whereasin the prior processes as much as 90% of the inorganic salts is commonlyretained in the oil layer and must be removed as well as possible bymechanical means.

The employment of the described alcohol or other oil-soluble,water-insoluble oxygen-bearing compound described offers the furtheradvantage that the oil-alcohol solution of the oil-soluble sulfonatesmay be readily water washed and rewashed without emulsificationdifilculties, should it appear desirable at any time so to treat the oillayer in order to remove the last traces of watersoluble sulfonate andinorganic salts from the oil solution. Additional quantities of theorganic diluent compound are usually required at each wash as agreater'proportion of the electrolyte is removed, unless adequatelylarge proportions of compound are initially used.

Another advantage in the employment of the alcohol or other describedoxygen-bearing compound is that it may be added to a sulfonateconcentrate before the addition of water, or either before or afterdilution with additional oil when such is employed, whereby the organicsolvent is present to take up the water-insoluble sulfonate as formed bymetathesis, or at other stages, or

.portions may be added at various stages as required.

In general, the greater the excess of calcium chloride used or thehigher the salts concentration in the water phase, the less the amountof alcohol required, but to take the fullest advantage of this in orderto conserve alcohol presents the danger of excessive contamination inthe event the settling or decanting operations are not perfect. I preferto use a larger volume of water and a smaller excess of calcium chloridetogether with a larger proportion of alcohol when a product of maximumpurity is desired, such as for use naval equipment.

As a specific example or one mode of practicing my invention, 4050 lbs.(477 gallons) sodium sulfonate of commerce, known as Grifiln ChemicalCompany's Gammanol L-100, containing approximately 64% sodium sulfonate,26% lubricating oil and 10% water and inorganic salts, was charged intoa steam heated kettle of 2200 gallons capacity. 1000 gallons of waterwas added and the kettle contents were heated to boiling and agitated toinsure thorough dispersion or the commercial sodium sulfonate. Then 600lbs. of commercial calcium chloride flakes (82% CaCh) dissolved ingallons of water was added to the kettle with agitation and continuedboiling. Then four (4) gallons of commercial fused oil (about iso-amylalcohol) was added with agitation to insure thorough mixing. Next, 500gallons of refined mineral oil (500 seconds Saybolt Universal viscosityat F.) was added and the kettle contents again brought to boiling withagitation.

Soon after the contents again reached boiling SEARCH RODN temperature,both heating and agitation were stopped and the kettle contents wereallowed to stand, 33212 hours. Two sharply defined layersdevelopedd'uring standing, and the bottom layer consisting of water anddissolved impurities was drawn oil accurately and discarded. Heat wasthen applied to the kettle and the retained upper layer was heated withagitation to 275 F. to remove i'usel oil and water. Agitation with drysteam for a few minutes at 250 F. was employed. As the kettle contentswere being heated, 50 lbs. powdered C9.(OH)2 were added to the kettle toinsure a neutral or alkaline product. Ai'ter dehydration at about 2751'. 1070 gallons oi the same oil as the 500 gallons added previously wasadded with agitation. The resulting blend was heated to 250 F. to 275 F.and passed through a Sharples Super-Centrifuge at the rate of 400gallons per hour. The centrifuge bowl was cleaned three times whilerunning the batch, first after 30 minutes. then after 2 hours, and atthe end of the run. The total solids removed from the centrifuge bowlweighed 18.6 lbs. and consisted largely of excess Ca(H)z.

A yield of 1980 gallons 01' clear calcium sulfonate concentrate wasobtained, containing approximately calcium sulfonate. Addition of 12parts of this concentrate to 88 parts of a well refined mineral oilblend of 53 seconds Saybolt Universal viscosity at 100 F. gave acompounded oil meeting the requirements for rust preventive oil forsmall arms as given in U. 8. Army specification 2-120. The addition 0112 to 18 parts of this concentrate to a number of different brands ofheavy duty crankcase ofl conforming to U. 8. Army specification 2-104Bgave in each case an interior engine preservative oil complying with U.S. Army Ordnance specification AXE-934. The addition of 20 parts oi thisconcentrate to 80 parts of refined mineral oil 01' 65 seconds viscosityat 210 F. gave a rust preventive oil complying with U. 8. Army Ordnancespecification AXS-674, Revision 2. The addition 01' 5 parts of theconcentrate along with 1 part tertiary amyl phenol sulfide to 94 parts01' a well refined motor oil blend, having a viscosity 01' 62 seconds at210 F. at :l a viscosity index of 78 gave a heavy duty crankcase oilcomplying with U. 8. Army specification 2-104B. The addition of 20 partsor the concentrate to 80 parts of petrolatum having a melting point of138 F. and a penetration of 210 gave a resulting rust preventivecompound complying with Army-Navy Aeronautical specification AN-C-124.The addition oi 10% to of the concentrate to sodium base greases usedfor automotive chassis lubrication not only imparted exceptionalresistance to corrosion from moisture and salt water immersion, but alsoimmaterial as a lubricant.

proved the resistance to disintegration by water to the point where suchmodified soda base greases compared satisfactorily in this respect withaluminum, barium, and lithium base greases. The addition of 5% to 20% ofthe concentrate to calcium, aluminum, barium, magnesium, zinc,

and lithium base greases. respectively, impTr'FFT both markedly improvedanti-rusting properties and reduced tendency to bleed or separate onstanding.

While my purified petroleum sulfonates or mahogany salts are usually thecalcium products, the invention includes also the preparation or otheralkaline earth metal suli'onates especially the barium salts and alsothe strontium salts. Such sulionates may be readily Pr pared byemploying water-soluble barium or strontium salts instead 01' calciumchloride or other water-soluble calcium salt. The processgilcgnvertingand puriapplicable to the production of water-insoluble, oil-solublesulfonates oi metals other than the alkalne earth metals. Such metalsinclude aluminum, zinc, magnesium lead, cobalt, nickel and the lik e. Inbrief. my process'inakes' it possible to manufacture efiiciently andeconomically the sulionates of any or the polyvalent metals.

For the purpose or production of rust preventives, as above indicated,the described waterinsoluble, oil soluble polyvalent. metal sulfonateconcentrate in oil is diluted with such carriers as may be desired forthe intended purpose. The diluent may be selected from any appropriatemineral oil lubricating fraction according to the ultimate use of theproduct. For example, the diluent may range anywhere from a very lightpetroleum fraction. such as one having a viscosity of 50 to 60 secondsSaybolt Universal at F. for low temperature work, up to one having aviscosity of 2000 seconds Saybolt Universal at 100 F. i correspondinggenerally with a lubricating oil oi an S. A. E. 70 grade) such as may berequired for high temperature lubrication in aircraft engines and thelike. In preparing such an oil, a quantity of the sulfonate productobtained by the above-described purification method will be employed toyield in the final product a proportion of the calcium sulfonate orother water-insoluble. oil-soluble metal suli'onate amounting to betweenabout 0.5% and about 8% based on the blended product. Ordinarily, asatisfactory working proportion will be about 3%, or between about 2%and about 4%.

Inasmuch as lubricating properties are possessed by the petroleumfractions employed for solution therein of the sulfonates purified bythe present improvement, the resultant rust-preventive products may besimultaneously employed as lubricants. In the case of aircraft and otherengines as above mentioned, where heavier grades of lubricating oils areemployed in producing the rust preventing composition, the engines maybe subsequently operated with the rust preventive I! desired, otherconstituents may be incorporated in such oils to adapt them to speciallubrication uses such as severe service conditions encountered inaircraft engines, Diesel engines, and the like. In those instances,other additives well known to thelubricating industry may be introduced,including (1) detergent soaps such as represented by oil-soluble calciumsoaps and similar metal soaps of synthetic carboxylic acids produced bythe oxidation oi parafiinic hydrocarbons. and (2) oxidation inhibitorssuch as sulfurized alcohols, sulfurized hydrocarbons, thiophosphates,phenolic thioethers, phosphites, suitable metal derivatives of thesematerials. and like materials known to th industry,

Similarly, purified sulfonates of the present in vcntion may be employedin the preparation of sulfonate-containing lubricating oil for severeservice uses and the like which are not necessarily required for rustpreventing purposes. Thus, typical lubricating oils may contain fromabout 0.5% to about 2%, for example 0.75%, of the purified alkalineearth metal sulfonate of this invention. together with from about'0.5%to 2% or 3%, for example about 1%. of oxidation inhibitors asabove-described, or detergent soaps as above-described. or otherwise, tomeet any given requirement. In many oi these instances,

Z lZU CROSS REFERENCE the gmplbyment of purified water-insoluble,oilsoiuhle alkaline earth metal sulfonates from pctroleum. asabove-described, are especially valuable in counteracting tendenciestoward undue corrosion in internal combustion engines, espe cially thoseof the severe service type such as the indicated aircraft and Dieselengines.

The purified sulfonates produced as described may be used in othercompositions than those above disclosed. For example, they may be usedas rust preventives in carriers which are normally solid and applied asfilms having appreciable thickness either by hot application or assolutions in readily volatilesolvents. Such sulfonates may be usedalso-in grease-like materials for rust preventing or lubricatingpurposes, or otherwise. For example, an appropriate quantity of theoil-sulfonate product may be added to petrolatum, and, if required, thiscomposition thinned with petroleum lubricating fractions to whateverconsistency desired. The petrolatum itself possesses lubricatingproperties.

When any of the products above-described are to be used under conditionswhere foaming is apt to be encountered, purified sulfonates may beproduced, as above-described, by employing the indicated octyl alcoholand terminating the subsequent expulsion of the octyl alcohol so as toleave around 0.5% to 2% of octyl alcohol in the oil-sulfonate solutionwhereby to impart antiioaming charcteristics. The same will be true ofany other organic solvent which is employed and possesses anti-foamingcharacteristics. I have also found that the prwence of 0.25% to 2% ofoctyl alcohol or other high molecular weight alcohol in the finishedlubricant increases very greatly the effectiveness of the sulfonateaddition in combating corrosion from hydrobromic acid. For example, theaddition of 2.5% calcium sulfonate to a heavy duty motor oil containing0.75% calcium soap of oxidized petroleum acids and 0.75% calcium salt oftertiary amyl phenol sulfide was sufiicient to protect the crankcaseinterior of engines against rusting from moisture condensation, but wasinsuillcient to protect against dilutes aqueous hydrobromic acid. Theaddition of 0.75% of octyl alcohol (z-ethylhexanal) to the foregoing oilcontaining 2.5% sulfonate, as described, gave perfect protection againsthydrobromic acid corrosion as required in Army-Navy Aeronauticalspecification AN- VV-C-576 and Army Ordnance specification AXS-934. Theaddition of the octyl alcohol in any amount to the heavy duty oildescribed, without the addition of the sulfonate, failed to correct thecorrosion from hydrobromic acid. Other alcohols, alcohol-esters such asCarbitoP' and Cellosolve (monoethyl ethers of diethylene and ethyleneglycol respectively, made by Carbide and Carbon Chemical Corporation),and their alkylated derivatives, may be used to increase theeffectiveness of the sulfonate addition in combating hydrobromic andhydrochloric acid corrosion of iron surfaces.

At present I have no theory regarding the operability of the indicatedclass of organic compounds which are useful for breaking the emulsionformed when sodium suli'onate is converted to alkaline earth or heavymetal sulfonates by metathesis, whereby good separation between the oillayer and water layer results. Obviously, it m not wholly a matter ofviscosity reduction imparted by the low viscosity of the solventdiluent, because petroleum naphtha, which possesses low purifying sodiumsulfonate.

is not effective. Nor are the water-soluble propyl alcohols effective,nor other lower molecular weight alcohols. conceivably, the results arederived as combined effects of the characteristics of low viscosity,oil-solubility, substantial waterimsolubility, and possibly even theeffect of very slight water-solubility which appears to be acharacteristic of the materials employed and defined as water-insoluble.

My process is not to be confused with the commonly used process ofconcentrating or purifying sodium sulfonate wherein crude sodiumsulfonate is extracted with methyl, ethyl, or isopropyl alcoholcontaining carefully controlled proportions of water. In the latterprocess, the solvent is miscible with water and immiscible with oil, andis designed to extract the sodium sulfonates away from the oil. Whileboth green acid and mahogany acid sodium soaps can be concentrated fromthe crude sodium sulfonates with water-iso-propyl alcohol mixtures, anytendency to separate green acid from mahogany acid soaps is in the wrongdirection. Water-isopropyl (or ethyl or methyl) alcohol mixtures have agreater solvent power for the green acid soaps than for the mahoganyacid soaps. The so-called purified sodium sulfonate produced in theconventional manner therefore usually has a higher ratio of green acidto mahogany acid soap than was present in the crude. sulfonate; whereasmy process gives a purified sulfonate in which the ratio of green acidto mahogany acid soap is less than was present in the crude sulfonate.In the conventional process, a portion of the more desirable mahoganyacid soaps is lost in the rejected oil phase, whereas in my process allof the more desirable mahogany acid soaps are recovered and the lessdesirable green acid soaps are expelled in the rejected water phase. Theamount of alcohol containing four or more carbons used in my process isfrom only a few tenths of a percent to 5 percent as a maximum, usually,based on the volume being processed, as compared with from 50% to 200%of aqueous alcohol solvent in the conventional process for Also, judgingfrom the small amount required of alcohol containing four or morecarbons per molecule, it would appear that the function of the alcoholin my process is not to act so much as a selective solvent as it is tobreak an otherwise stable oil-continuous emulsion, and to permitwater-soluble impurities to be expelled in an easily removed waterphase.

While I have described my process as being applicable to petroleumsulfonates produced by sulfuric acid treatment of petroleum fractions,my process is also applicable to sulfonates produced synthetically bysulfonation of hydrocarbons or other compounds from coal tar products orany other source. Also mymis applicable to sulfates (often calledsulfonates) produced by re acting sulfuric acid or sulfur trioxide withalcohols and/ or unsaturated compounds belonging to the classes ofhydrocarbons acids, esters, ketones ethers, glycerides, waxes, etc.

It is to be understood that, in view of the above disclosures, othermodifications will become apparent to those skilled in the art to whichthese improvements pertain. Therefore, all modifications within thescope of the appended claims are intended to be 'protected thereby.

viscosity and is water-insoluble and oil-soluble,

I claim as my invention:

1. In a process of producing water-insoluble, oil-solublepolyvalent-metal hydrocarbon suli'oacts, the steps which comprise:forming a mix- SUXKUH KUU ture containing water, said polyvalent metalsulfonate-iandan emulsion-breaking, oil-soluble liquid compoundconsisting of carbon, hydrogen and oxygen and containing four to abouteight carbon atoms per molecule to facilitate separation of awater-insoluble sulfonate-containing phase from an aqueous phase; andrecovering the sulfonate phase.

2. The process of claim 1 wherein the mixture containing saidemulsion-breaking liquid is heated approximately to the boiling point ofthe mixture to facilitate said separation.

3. The process of claim 1 wherein said emulsion-breaking liquid is analiphatic alcohol.

4. The process oi claim 1 wherein said emulsion-breaking liquid isabutyl alcohol.

5. The process of claim 1 wherein said emulsion-breaking liquid is anamyl alcohol.

6. The process of claim 1 wherein an alkaline earth metal hydroxide isheat d with said separated sulfonate-containing phase in the presence ofsaid emulsion-breaking liquid to render said sulionate alkaline.

7. The process of claim 1 wherein said polyvalent-metal sulfonate is analkaline earth metal sulionate.

8. The process of claim 1 wherein the quantity of emulsion-breakingliquid employed is about 0.2% to 10% of the mixture.

9. A process as in claim 1 wherein the separated sulfonate-containingphase is washed with water in the presence of said emulsion-breakingliquid.

10. In a process of producing water-insoluble, oil-solublepolyvalent-metal hydrocarbon sulfonate, the steps which comprise:forming a mixture containing water, said polyvalent-metal sulfonate, apetroleum oil of lubricating viscosity and anemulsion-breaking,oil-soluble liquid compound consisting of carbon, hydrogen and oxygenand containing four to about eight carbon atoms per molecule, saidwater, sulfonate and oil tending to form an oil continuous emulsion, andsaid emulsion-breaking liquid facilitatingseparation of awater-insoluble sulfonate and petroleum oil containing phase from anaqueous phase; and recovering the sulfonate and oil containing phase.

11. The process of claim 10 wherein the mixture containing saidemulsion-breaking liquid is heated approximately to the boiling point ofthe mixture to facilitate said separation.

12. The process of claim 10 wherein said emulsion-breaking liquid is analiphatic alcohol.

13. The process of claim 10 wherein said emulsion-breaking liquid is abutyl alcohol.

14. The process of claim 10 wherein said emulsion-breaking liquid is anamyl alcohol.

15. The process of claim 10 wherein an alkaline earth metal hydroxide isheated with said separated sulfonate 011 containing phase in thepresence of said emulsion-breaking liquid to render said sulfonatealkaline.

16. The process of claim 10 wherein said polyvalent-metal suli'onate isan alkaline earth metal sulionate.

17. The process of claim 10 wherein the quantity of emulsion-breakingliquid employed is about 0.2% to 10% of the mixture.

18. A process as in claim 10 wherein the separated sulfonate oilcontaining phase is washed with water in the presence of saidemulsionbreaking liquid.

19. A process of producing oil-soluble, waterinsoluble, polyvalent-metalpetroleum type sulfonate, substantially free from water-solubleconstituents, comprising: preparing a mixture in water of oil-soluble.water-soluble, alkali metal petroleum sulfonate containing petroleumoil; supplying to said mixture an oil-soluble, organic emulsion-breakingliquid compound consisting of carbon, hydrogen and oxygen and containingfrom four to about eight carbon atoms per molecule; also supplying tosaid mixture a water-soluble, polyvalent metal salt to convert saidalkali metal sulfonate to said oil-soluble, water-insolublepolyvalent-metal sulfonate, whereby said liquid compound facilitatesseparation of an oil phase containing said polyvalentmetal sulfonate andoil from an aqueous phase containing said water and water-solubleconstituents; and recovering the resultant polyvalentmetal sulfonate andoil phase.

20. A process in accordance with claim 19, in which theemulsion-breaking compound is introduced into said mixture prior tointroducing said polyvalent metal salt.

21. A process in accordance with claim 19 in which the emulsion-breakingcompound is introduced into said mixture after formation of saidpolyvalent-metal sulfonate.

ULRIC B. BRAY.

REFERENCES CITED The following references are of record in the the ofthis patent:

UNITED STATES PATENTS Number Name Date 2,140,263 Kessler et al Dec. 13,1938 2,166,117 Blumer July 18, 1939 2,168,315 Blumer Aug. 8, 19392,246,374 Lohman et al. June 17, 1941 2,261,047 Assefl' Oct. 28, 19412,285,752 Van Ess June 9, 1942' 2,304,230 Archibald et a1 Dec. 8, 19422,307,953 Potter Jan. 12, 1943 2,316,719 Russell Apr. 13, 1943 2,361,476Higbee et al. Oct. 31, 1944 2 6 U 4 2 9 cross REFEPENCE sum ROOMCertificate of Correction Patent No. 2,453,690. November 16, 1948.

ULRIO B. BRAY It is hereby certified that errors appear in the printedspecification of the above numbered patent requiring correction asfollows:

Column 9, line 46, for the word dilutes read dilute; line 48, forhexanal read hezanol; line 57, for alcohol-esters read oralcohol-ethers;

and that the said Letters Patent should be read with these correctionstherein that the same may conform to the record of the case in thePatent Oflice.

Signed and sealed this 29th day of March, A. D. 1949.

THOMAS F. MURPHY,

Assistant Oonwm'asioner of Patents.

Ar Q Ma. a

